1. Field of the Invention
This invention relates to a fifth wheel coupling for joining sections of an articulated vehicle.
2. Description of the Background of the Invention
Sections of an articulated vehicle, such as the sections of a tractor-trailer combination vehicle, are commonly coupled together by a fifth wheel coupling, which includes a strike plate (normally mounted on the tractor) with a locking mechanism that captures a kingpin (normally mounted on the trailer). The fifth wheel coupling permits the tractor to pivot relative to the trailer in a manner well known to those skilled in the art. Normally, the only connection between the tractor and trailer is through the kingpin, so that if the locking mechanism fails, either through a broken component or because the locking mechanism was improperly latched, the sections of the vehicle may separate from one another, resulting in an extremely dangerous situation in which the trailer breaks away from the tractor and cannot be controlled. Obviously, in such a situation, property damage and injuries or death of bystanders is likely.
Accordingly, a safety latch that prevents unwanted separation between the tractor and trailer is desirable. However, to be effective, the latch must be engaged whenever the vehicle sections are coupled, but the safety latch must be easily inactivated to permit separation of the vehicle sections when uncoupling is desired.